(DRAFT) - Taxonomy
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
TAXONOMY
NAME - SQUIRREL, FOX, DELMARVA PENINSULA
OTHER COMMON NAMES - SQUIRREL, FOX, DELMARVA PENINSULA; SQUIRREL, GRAY; SQUIRREL, CAT; SQUIRREL, STUMP-EARED; SQUIRREL, FOX, BRYANT'S;SQUIRREL, FOX, PENINSULA; SQUIRREL, FOX, DELMARVA;SQUIRREL, GRAY and BIG
ELEMENT CODE -
CATEGORY - Mammals
PHYLUM AND SUBPHYLUM - CHORDATA,
CLASS AND SUBCLASS - MAMMALIA,
ORDER AND SUBORDER - RODENTIA,
FAMILY AND SUBFAMILY - SCIURIDAE,
GENUS AND SUBGENUS - SCIURUS,
SPECIES AND SSP - NIGER, CINEREUS
SCIENTIFIC NAME - SCIURUS NIGER CINEREUS
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Delmarva Peninsula Fox Squirrel
Sciurus niger cinereus Linnaeus, 1758
KINGDOM: Animal GROUP: Mammal
PHYLUM: Chordata CLASS: Mammalia
ORDER: Rodentia FAMILY: Sciuridae
Distinguishing characteristics: Teeth 1/1, 0/0, 1/1, 3/3 = 20;
coloration uniform light grizzled-gray above with steel blue cast;
belly and feet white; tail with pronounced black stripe on outer
edges. Melanistic form occurs in which belly and feet are blackish.
Can be distinguished from gray squirrel mainly by larger size and
reduced dentition. Mean measurements of 5 adults from Dorchester
county, MD: total length 579 mm (560-605 mm); tail 273 mm
(263-285 mm); hind foot 77 mm (73-81 mm) (01).
Taxonomy of Delmarva Peninsula fox squirrel confused with that of
the gray squirrel (Sciurus carolinensis pennsylvanicus Ord) and other
subspecies of fox squirrels; partly due to the absence of a Delmarva
fox squirrel holotype (02), and partly due to proliferation of
Delmarva fox squirrel common name synonyms, including gray squirrel,
cat squirrel, stump-eared squirrel (03), Bryant's fox squirrel and
peninsula fox squirrel (04). Type specimen of Delmarva fox squirrel
Taxonomy - 1 (DRAFT) - Taxonomy
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
synonym Macroxus neglectus Gray 1867 was collected near Wilmington,
DE about 1865 (03,05) and subsequently lost (06,34). The neotype
named by Barkalow in 1956 (02), restricting type locality to
Cambridge, Dorchester Co., MD (01,02). Neotype No. 58158, Univ. of
Michigan Museum of Zoology, Mammal Collection (02). Complete
taxonomic history presented by Barkalow in 1954 (07); abbreviated
history with taxonomic synonyms listed below. Scientific names are
listed as follows:
Sciurus niger cinereus Linnaeus;
Sciurus niger cinereus Linnaeus, 1758 (07);
Sciurus cinereus Linnaeus, 1758:64 (08 as cited in 07);
Macroxus neglectus Gray, 1867:425 (09 as cited in 07);
Sciurus niger cinereus Allen, 1877:717 in part. (10 as cited in 07);
Sciurus ludovicianus neglectus Nelson,1900:13:169 (11 as cited in 07);
Sciurus niger neglectus Osgood, 1907:20:45 in part. (12 as cited 07);
Sciurus niger branti Bailey, 1920:1:1 (13 as cited in 07);
Sciurus niger neglectus Poole, 1944:25:315 (03 as cited in 07).
Common name synonyms are listed as follows:
Squirrel, fox, Delmarva Peninsula;
Squirrel, gray (03,15);
Squirrel, cat (03,15);
Squirrel, stump-eared (03,15);
Squirrel, fox, Bryant's (04,15,16);
Squirrel, fox, peninsula (04);
Squirrel, fox, Delmarva (05,14);
Squirrel, gray, big (15).
Taxonomy - 2 (DRAFT) - Status
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
STATUS
Coded Status
Maryland; Federal Endangered
Maryland; State Listed
Virginia; Federal Endangered
Virginia; State Listed
E: Federal Endangered
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Delmarva Peninsula fox squirrel (Sciurus niger cinereus) has
been designated an Endangered species pursuant to the Endangered
Species Act of 1973 (50 CFR 17.11;P.L. 93-205, 87 Stat. 884; 16 U.S.C.
1531-1540), as amended. The subspecies has this status wherever found
including the States of Delaware, Maryland, New York, New Jersey,
Pennsylvania, and Virigina.
Special rules concerning a nonessential experimental population
in Sussex County, DE, for this subspecies can be found in 50 CFR
17.84(a). These special rules allow this population to be treated as
Threatened. This status provides greater management flexibility and
in all practicality gives Delaware management responsibility for this
population.
This subspecies is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import,
export, transport, sell, receive, acquire, or purchase any wild animal
(alive or dead including parts, products, eggs, or offspring):
(1) in interstate or foreign commerce if taken, possessed,
transported or sold in violation of any State law or
regulation; or
(2) if taken or possessed in violation of any U.S. law,
treaty, or regulation or in violation of Indian tribal law.
It is also unlawful to possess any wild animal (alive or dead
including parts, products, eggs, and offspring) within the U.S.
territorial or special maritime jurisdiction (as defined in
18 U.S.C. 7) that is taken, possessed, transported, or sold in
violation of any State law or regulation, foreign law, or Indian
tribal law.
RESPONSIBLE FEDERAL AGENCIES:
Status - 1 (DRAFT) - Status
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
NPS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for conservation (Nat. Park System Organic Act -
16 U.S.C. 1, 2-3)/management/recovery on National
Park Service lands. Taking, possessing, or disturbing
of Federally listed species is prohibited on NPS lands
(36 CFR 2.1, 2.2, and 2.3).
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
conservation of the species.
STATE STATUSES AND LAWS:
STATE: Delaware, New Jersey, New York, Pennsylvania
DESIGNATED STATUS: Recognized Endangered
ADMINISTRATIVE AGENCY: DE Division of Fish and Wildlife
NJ Dept. of Environmental Protection;
Div. of Fish, Game and Wildlife
NY Dept. of Environmental Conservation
PA Game Commission
STATE STATUTE: DE - 7 DE Code Annot., Sec. 601.
NJ - NJ Annot. Code 7:25-20.1, 20.2, Jan. 14, 1981
NY - 6 NY Code, Rules and Regs. 182.5,
Apr. 30, 1983
PA - 58 Pennsylvania Code, Sec. 147.1, 147.21,
March 1983
STATE: Maryland
DESIGNATED STATUS: Threatened
ADMINISTRATIVE AGENCY: Maryland Department of Natural Resources
STATE STATUTE: Maryland Nongame and Endangered Species
Conservation Act of 1975, 10-2A01 et seq.
Maryland Natural Resources Code Annotated, Sec.
4-2A-01 to 4-2A-09, 10-2A-01 to 10-2A-09; Code
of Maryland Regulations 08.03.01.43, Supp. 4
STATE: Virigina
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Virigina Commission of Game and Inland
Fisheries
STATE STATUTE: Code of Virigina of 1950, Stat. 29-230 to 29-237
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
This species is listed as "endangered" in the 1986 edition of the
IUCN Red List of Threatened Animals (under the common name of
Delmarva Fox Squirrel). This species is also listed as "endangered"
Status - 2 (DRAFT) - Status
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
in the Western Hemisphere Convention Annex.
ECONOMIC STATUSES:
This species may have recreational value to naturalists.
67/03/11:32 FR 04001/ - Listed as Endangered
75/05-16:40 FR 21499/21500 - Notice of Intent (Crit. Hab.)
79/05/21:44 FR 29566/29577 - Notice of Status review
84/09/13:49 FR 36418/36420 - Experimental Status of Introduced Pop.
Status - 3 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
INLAND AQUATIC
SOCIETY OF AMERICAN FORESTRY TYPES
SAF TYPE STAGE CLOSURE
Loblolly Pine-Shortleaf Pine mature tree
Loblolly Pine-Shortleaf Pine Old Growth
Shortleaf Pine-Oak mature tree
Shortleaf Pine-Oak Old Growth
mature tree
Old Growth
mature tree
Old Growth
LAND USE -
Cropland and Pasture
Orchards, Groves, Vineyards, Nurseries,
Deciduous Forest Land
Evergreen Forest Land
Mixed Forest Land
Forested Wetland
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Palustrine FO
COMMENTS ON HABITAT ASSOCIATIONS -
The Delmarva fox squirrel is associated predominantly with
small stands of mature timber with an open understory, largely in
agricultural areas (04,05,14,17,18,19). The Delmarva fox squirrel
does occur in areas with dense undergrowth, but under those conditions
is forced to compete with the gray squirrel (04). Hedgerows or
fencerows are often used as travel lanes between woodlots (06). The
Delmarva fox squirrel is also associated with savanna or parklike
areas (04,14); lowland, swampy areas (05,16,22 as cited in 05); and
narrow tree zones along rivers and streams (04,14). The association
with water is indirect, however, through the effect of water on
vegetation (i.e., less understory, and difficulty in harvesting timber
in wet areas) (05). Inhabited forested areas are most often a mixture
of mature hardwoods and conifers (01,14,16); tree groups mentioned in
literature include oak (01,14,16,19), hickory (01,23 as cited 05), gum
(16,19), beech (19), walnut (14), and loblolly pine (01,14,16,19).
Delmarva fox squirrels do sometimes occur in pure loblolly pine stands
(30), and some authors have indicated old-growth loblolly pine forests
are the preferred habitat of the Delmarva fox squirrel (01,16,24 as
cited in 05). Others point out that the original range of the
Delmarva fox squirrel extended beyond the range of the loblolly pine
(18,21 as cited in 04). In a study on MD's Eastern Shore, Taylor (05)
found no significant difference in the ratio of coniferous to
deciduous trees between areas inhabited by the Delmarva fox squirrel
and areas excluding the Delmarva fox squirrel (n=50). The current
range of the Delmarva fox squirrel includes forest regions such as the
oak-pine forest (05,25), loblolly-shortleaf pine forest (25), and
oak-gum-cypress forest (25). Historically, the Delmarva fox squirrel
Habitat Associations - 1 probably occurred in the oak-hickory forest also (23 as cited in 05,
25).
As stated above, the Delmarva fox squirrel is associated with
agricultural land. Delmarva fox squirrels are quite terrestrial, and
are often seen feeding far into open fields (04). The most prevalent
crops associated with the Delmarva fox squirrel are corn, soybeans,
and small grains (05,19). They are also known to feed in "other field
crops" and orchards (04,17). Corn, soybeans, wheat and barley are
common crops within the current range of the Delmarva fox squirrel
(26).
Unique features associated with the Delmarva fox squirrel include
tree cavities and dead snags which may provide denning sites. The
Delmarva fox squirrel dens mostly in the winter but builds leaf nests
more commonly in the summer (06). As mentioned above, the Delmarva
fox squirrel uses hedgerows or treed fencerows as travel lanes between
woodlots (06).
Habitat Associations - 2 (DRAFT) - Food Habits
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
FOOD HABITS
TROPHIC LEVEL -
OMNIVORE
LIFESTAGE FOOD FOOD PART
General Myxomycophyta
General
General Forb Flowers/Fruit/Seed
General Deciduous Shrubs-Leaves/Twigs
General Deciduous Shrubs-Flowers/Fruit/Seed
General Tree-Bark/Cambium
General Deciduous Trees-Leaves/Twigs
General Deciduous Trees-Flowers/Fruit/Seed
General Evergreen Trees-Flowers/Fruit/Seed
General Aves
General Arthropods
Food Habits - 1 (DRAFT) - Environment Associations
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Snags: Unknown
G Tree Cavities: Unknown
G Availability of fence rows: roadside ditches and grassy
Environment Associations - 1 (DRAFT) - Life History
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
LIFE HISTORY
FOOD HABITS:
The Delmarva fox squirrel feeds heavily on the fruit of trees
such as oak, hickory, beech, walnut and loblolly pine (01,04,14,16).
Some authors indicate a preference for loblolly seeds by the Delmarva
fox squirrel (01,16), but the species does not consume these to the
exclusion of fruits of deciduous trees (05). The Delmarva fox
squirrel will consume large amounts of the above items during the
fall, becoming fat in preparation for the scarcity of food during the
winter months (14). During spring, the Delmarva fox squirrel will
feed extensively on tender green twigs (16), buds and flowers of
trees, large quantities of fungi (including some poisonous mushrooms),
insects, fruit, seeds, and occasionally bird eggs and young (04,14).
The Delmarva fox squirrel will utilize agricultural fields, and
is sometimes observed foraging in open fields a mile or more from the
nearest forest (14). Corn is particularly exploited by the species
(05), although they seldom cause significant damage to corn or other
domestic crops (01). Like fox squirrels in other parts of the
country, the Delmarva fox squirrel will also consume soybeans, wheat,
barley, oats, apples and other field and fruit crops (05).
HOME RANGE/TERRITORY:
The home range of the fox squirrel averages about 10 acres, but
in the course of a year an individual may travel over 3 or 4 times
that area (30). Flyger and Smith (1980) observed an average home
range of 30 hectares for Delmarva fox squirrels in Talbot county, MD
(19). Home range may vary seasonally with food availability, though
definitive information is lacking on the subject (34). The Delmarva
fox squirrel is nonterritorial, although the female may chase other
squirrels from the immediate vicinity of the nest during the breeding
season (34).
PERIODICITY:
Fox squirrels are diurnal and are most active in the morning and
early afternoon (30), generally returning to their dens or nests
before sundown (29). Activity is decreases during cold or inclement
weather. In unusually cold weather, the squirrel may hole up" and not
leave its nest for a week or more (30).
MIGRATION PATTERNS:
The Delmarva fox squirrel is non-migratory. One author states:
"There are no records of mass migrations as those recorded for other
squirrels such as the southern gray. Perhaps this is because hunting
pressure together with the elimination of a large part of its best
breeding grounds has so reduced the population that migrations have
never become a necessity, at least during more recent times" (16).
COVER/SHELTER REQUIREMENTS:
Over-age trees with hollows and holes are preferred as den sites
by the Delmarva fox squirrel (30). These dens, (which would need to
be large enough to accomodate up to a 2 to 2.5 pound squirrel) provide
maximum safety for young and the best protection from cold and wet
Life History - 1 (DRAFT) - Life History
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
weather (30). Availability of adequate denning sites increases the
survival of young and adults(14). However, in the absence of tree
hollows, the Delmarva fox squirrel will construct leaf nests, usually
in pines or oaks (30). Dens or nests are used year round for
protection from predation and the weather.
REPRODUCTIVE SITE REQUIREMENTS:
The Delmarva fox squirrel will usually raise her young in tree
dens, but when these are unavailable, will construct leaf nests
similar to those of gray squirrels (14,30). Tree dens are more
commonly used in winter and leaf nests in the summer (04). The
Delmarva fox squirrel has been known to use nesting boxes attached to
tree trunks approximately 6-7 meters above ground (19). One author
states that the Delmarva fox squirrel builds nests near the tips of
branches in old pines, from 9 to 15 meters above ground (01,29).
However, Delmarva fox squirrels are known to build leaf nests in
deciduous trees also (29,30), and nests may occur in crotches in the
trunk (30). Nests are constructed of leaves and twigs from the tree
in which they are located (30). Dozier and Hall (1944) described a
nest in a pine tree as oval or somewhat flattened in shape,
constructed of twigs with the needles still attached and a few
scattered oak leaves (16).
REPRODUCTIVE CHARACTERISTICS:
Delmarva fox squirrel females raise the young alone (08,14).
Breeding season is extended, with peaks in February and March, and in
July and August (04). The crop of young is usually larger in the late
winter (30). Females may reach maturity at 8 or 9 months (14),
and may breed at 10 to 11 months (04,14). Older females may breed
twice a year, while yearlings breed only once (30). From 1 to 6 young
are born after a gestation of about 45 days (28,30). Average litter
size is 3 or 4 young (14,30). Food availability seems to govern the
size and number of litters (04).
PARENTAL CARE:
The Delmarva fox squirrel is polygamous and the female raises the
young alone (14). Young are born naked and blind. Eyes open at 5
weeks and weaning takes place at 9 to 12 weeks. The Delmarva fox
squirrel is not sensitive to human disturbance, and young can be
handled in the nest with minimal adverse effect. The female will not
abandon her young, but may move the young to a different nest if
disturbed (14). Family bonds are dissolved at weaning (34).
POPULATION BIOLOGY:
Direct competition with gray squirrels (Sciurus carolinensis) for
food and denning sites is a significant limiting factor currently
facing the Delmarva fox squirrel (04,14). Destruction of preferred
habitat of the Delmarva fox squirrel (small woodlots of mature, mixed
hardwood/coniferous forest with little understory) has forced the
subspecies into suboptimal areas dominated by gray squirrels (04,05,
14). During severe winters, heavy mortality can result from
debilitating epidemics of mange (Cnemidoptes) (14). Additional
mortality is caused by accidental hunting kills and road kills, but
Life History - 2 (DRAFT) - Life History
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
these are probably not significant limiting factors (14).
Survival and mortality rates are not known. Eastern fox
squirrels (Sciurus niger) are known to live 10 years or more (31).
The sex ratio of the Delmarva fox squirrel population is probably
close to 1:1 (34). A sample of Delmarva fox squirrels (n=124) using
nesting boxes on Chincoteague NWR between 1977 and 1982 was 54
percent male (32).
The Delmarva fox squirrel exhibits good potential for recovery
(14). The Delmarva fox squirrel recovery team (1979) believes that
the status of the Delmarva fox squirrel could be changed from
endangered to threatened if existing suitable habitat is maintained
and 10 new colonies are established outside the known range of the
Delmarva fox squirrel (as delineated in 1979) (14). Secure status
(e.g., removal of the Delmarva fox squirrel from threatened status)
could be achieved by the establishment of 20 additional prospering
colonies (in addition to above 10) outside the delineated range (14).
In order to acheive this goal Delmarva fox squirrel translocations
have been attempted within the states of Maryland and Virginia, and
from Maryland to Virginia, Delaware and Pennsylvannia. In most
cases, the success of the transplanted animals has been monitored
via radio telemetry, live-trapping and nest box checks. Transplants
have been varyingly successful; reproduction has been confirmed at
most sites where work has been ongoing for at least three years,
provided no profound habitat changes have occurred. At present,
there are two successfully transplanted populations in Virginia, one
in Delaware, and three in Maryland. It is still too early to
determine success at an additional three sites in Maryland, one in
Delaware, and one in Pennsylvania (38).
SPECIES INTERRELATIONSHIPS:
Direct competition with eastern gray squirrels (Sciurus
carolinensis) for food and denning sites is a significant limiting
factor currently facing the Delmarva fox squirrel (04,05,14).
Reductions of gray squirrel populations in areas of coexistence with
the Delmarva fox squirrel would directly benefit the Delmarva fox
squirrel population (14,19,33) although some authors consider gray
squirrel population reductions impractical (19,33).
OTHER LIFE HISTORY DESCRIPTORS:
There are no estimates of the total number of Delmarva fox
squirrels. Based on the most recent surveys, the largest populations
of this squirrel occur on USFWS National Wildlife Refuges or
State-owned or controlled lands. In 1987, roughly 800 Delmarva fox
squirrels were estimated to occur on 4 Federal National Wildlife
Refuges: Chincoteague NWR (140), Eastern Neck NWR (100-150),
Blackwater NWR (550), and Prime Hook NWR (10-20) (35,36,38).
Life History - 3 (DRAFT) - Management Practices
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Land Acquisition
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Creating Artificial Habitat/Nesting Structure
Beneficial Restricting Timber Harvest
Beneficial Maintaining Later Stages of Succession
Beneficial Timber Harvesting
Beneficial Controlling/Removing Native Vegetation
Beneficial Transplanting wild animals
Beneficial Supplemental Feeding
Beneficial Restricting Poaching
Beneficial Controlling/Removing Native Vertebrates
Adverse Rural Residential/Industrial Areas
Existing Rural Residential/Industrial Areas
Adverse Recreational development
Existing Recreational development
Adverse Highway/Railroads
Existing Highway/Railroads
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Developing/maintaining stream bank vegetation
Existing Developing/maintaining stream bank vegetation
Adverse Shoreline modification/development
Existing Shoreline modification/development
Adverse Incidental Capturing/Killing
Existing Incidental Capturing/Killing
Adverse Sport Hunting/Fishing
Existing Sport Hunting/Fishing
Adverse Food Supply Reduction
Existing Food Supply Reduction
Adverse Disease
Existing Disease
Adverse Parasites
Existing Parasites
Adverse Predation
Existing Predation
Adverse Competition
Existing Competition
Adverse Applying herbicides
Existing Applying herbicides
Adverse Applying pesticides
Existing Applying pesticides
Adverse
Existing
Adverse Vegetation Composition Changes
Existing Vegetation Composition Changes
Adverse Forest Alteration
Existing Forest Alteration
Management Practices - 1 (DRAFT) - Management Practices
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
RESULT MANAGEMENT PRACTICE
Adverse Harvesting
Existing Harvesting
COMMENTS ON MANAGEMENT PRACTICES -
The range of the gray squirrel (Sciurus carolinensis) almost
entirely overlaps that of the Delmarva Peninsula fox squirrel (05,06,
14). In areas where they coexist, the Delmarva fox squirrel prefers
small stands of large timber with an open understory, large in
agricultural areas (05,14,17,18,19). The gray squirrel prefers larger
forested tracts with dense understory (05,14,17). This differential
habitat preference may be due in part to historical influences of
natural predation, the open habitat being an advantage to the less
agile, more terrestrial fox squirrel(05). Whatever the reasons for
the habitat preference, it resulted in a restriction in range and
numbers of the Delmarva fox squirrel as habitats were altered by man
(19,20). The potential positive effects of agricultural development
(i.e., through increased food sources and creation of small wood lots)
have been offset by the negative effects of lumbering and hunting
(05).
Lumbering has removed much of the old growth timber preferred by
the Delmarva fox squirrel (01,04,05,14,15,16,17). Length of current
timber rotations result in dense heavy understories, selecting against
the Delmarva fox squirrel (05,14). Loss of old growth timber also
removes abundant, concentrated food sources typical of older, larger
hardwoods (05). Trends toward replacement of hardwoods with pure pine
stands also reduces food sources and provides poor quality habitat
(05). Because of its low numbers and patchy distribution, the
Delmarva fox squirrel cannot maintain a hold or colonize new areas
when forced to compete directly with the more numerous gray squirrel
in less than optimal habitat (04,05,14,17).
Many residents of the Eastern Shore of Maryland consider the
Delmarva fox squirrel to be "just a big gray squirrel"(05). In the
past, the Delmarva fox squirrel was widely hunted (05,15,16), and some
hunting mortality probably continues today (04,05) due to the
difficulty in immediately distinguishing the Delmarva fox squirrel
from the gray squirrel.
Construction and development in response to increased human
population on the Eastern Shore is also destroying Delmarva fox
squirrel habitat (04,05,17,20). The Delmarva fox squirrel is often
found in narrow tree zones along rivers, streams, and bays (04,14),
and development (i.e., transportation routes, rural housing areas,
industrial areas, recreation areas, and agriculture) of this edge
habitat are all factors contributing to habitat loss, and this is
detrimental to the Delmarva fox squirrel's existence.
Although no losses of Delmarva fox squirrels to
pesticide/herbicide poisoning have been documented, consumption of
seed grains treated with poisons could, on occasion, cause mortality.
(14). Due to the amount of time the Delmarva fox squirrel spends on
the ground, road kills are a minor source of mortality (04,14). The
Delmarva fox squirrel becomes thin and emaciated during severe winter
Management Practices - 2 (DRAFT) - Management Practices
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
Management Practices - 3 (DRAFT) - Management Practices
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
conditions. At such times, mange (Cnemidoptes), which is probably
endemic, develops into a debilitating epidemic resulting in heavy
mortality (14).
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1983. The Delmarva Peninsula
Fox Squirrel Recovery Plan. U.S. Fish and Wildlife Service, Newton
Corner, MA. 49 pp.
Basic management practices listed in Delmarva Peninsula fox
squirrel Recovery Plan:
1. Existing Delmarva fox squirrel habitat should be protected by
planned forest cutting and the prevention of excessive understory
development.
2. Adequate number of dens should be assured by protection of den
trees and/or placement of nest boxes.
3. Excessive competition from gray squirrels and other animals should
be reduced in release areas, islands, or under other circumstances
where practical.
4. Inordinate mortality should be reduced by protection from hunting,
poaching and predation (such as dogs).
5. An adequate and dependable food supply should be provided,
including, in some cases, the establishment of food plots of corn or
soybeans.
6. Small populations of Delmarva fox squirrels should be translocated
to reestablish the subspecies into suitable, unoccupied habitat within
its historic range. The experimental population designation may be
used to encourage State participation.
Other management practices include:
- Increase law enforcement surveillance at release sites.
- Acquire or lease adequate lands for gene pool maintenance.
- Encourage public support through use of news media, lectures,
leaflet distribution, etc.
- Establish management agreements with private landowners when
possible.
Research needed into response of Delmarva fox squirrels to various
habitat treatments and effectiveness of nest boxes in increasing
denning sites.
A recovery activity has already included the release of a
nonessential experimental population in Delaware. This action was
taken to reestablish the species within its historic range.
Additional reintroductions are being considered to expand the
population even further. This is consistent with the goal identified
in the Recovery Plan.
Management Practices - 4 (DRAFT) - Management Practices
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
Management Practices - 5 (DRAFT) - References
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Paradiso, J.L. 1969. Mammals of Maryland. North American Fauna
No. 66. U.S. Dept. of Interior, Bureau of Sport Fisheries and
Wildl., U.S. Gov. Printing Office, Washington, D.C. 193 pp.
02 Barkalow, F.S., Jr. 1956. Sciurus niger cinereus Linne neotype
designation. Proc. Biol. Soc. of Washington, 69:13-20.
03 Poole, E.L. 1944. The technical names of the northeastern fox
squirrels. J. Mammal., 25:315-317.
04 U.S. Dept. of Interior. 1980. Selected vertebrate endangered
species of the seacoast of the United States: The Delmarva
Peninsula fox squirrel. U.S. Fish and Wildlife Service, Biological
Services Program. FWS/OBS-80/01.37. 5 pp.
05 Taylor, G.J. 1973. Present status and habitat survey of the
Delmarva fox squirrel (Sciurus niger cinereus) with a discussion of
reasons for its decline. Proc. 27th Ann. Conf. Southeastern Assoc.
of Game and Fish Commissioners. Pp. 278-289.
06 Taylor, Gary J. 1983. Pers. comm. Maryland Wildlife
Administration, Wye Mills Work Center, P.O. Box 68, Wye Mills, MD
21679. (301) 827-8612.
07 Barkalow, F.S., Jr. 1954. Status of the names of Sciurus niger
cinereus Linnaeus and Sciurus niger vulpinus Gmelin. J. Elisha
Mitchell Sci. Soc. of Baltimore, 70(1):19-26.
08 Linnaei, Caroli. 1758. Systema naturae. Holmiae, Laurentii,
Salvii, Tomus I, Editia Decima, Reformata. P. 64.
09 Gray, J.E. 1867. Synopsis of the American squirrels in the
collection of the British Museum. Ann. and Mag. Nat. Hist. 20
(Serial 3):415-436.
10 Coues, E. and J.A. Allen. 1877. Monographs of North American
Rodentia. U.S. Geol. and Geog. Surv. Territories 11.
11 Nelson, E.W. 1900. The correct name for the eastern form of the
fox squirrel. Proc. Biol. Soc. of Washington 13:169-170.
12 Osgood, W.H. 1907. Some unrecognized and misapplied names of
American mammals. Proc. Biol. Soc. of Washington 20:43-52.
13 Bailey, H.H. 1920. A new fox squirrel from the eastern shore of
Maryland. Bailey Mus. and Library of Nat. Hist. Bull. No. 1.
14 U.S. Fish and Wildlife Service. 1983. The Delmarva Peninsula
Fox Squirrel Recovery Plan. U.S. Fish and Wildlife Service, Newton
Corner, MA. 49 pp.
15 Mansueti, R. 1952. Comments on the fox squirrels of Maryland.
MD. Naturalist 22:30-41.
16 Dozier, H.L. and H.E. Hall. 1944. Observations on the Bryant fox
squirrel, Sciurus niger bryanti Bailey. MD Conservationist
21:1-12.
17 Taylor, G.J. [n.d.] Maryland's Delmarva fox squirrel. MD Dept.
Nat. Resour. Fact Sheet. 2 pp.
18 Taylor, G.J. and V. Flyger. 1973. Distribution of the Delmarva
fox squirrel (Sciurus niger cinereus) in Maryland. Chesapeake Sci.
14:59-60.
19 Flyger, V. and Deborah A. Smith. 1980. A comparison of Delmarva
fox squirrel and gray squirrel habitats and home range. Trans. of
References - 1 (DRAFT) - References
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
the Northeast Section of the Wildl. Soc., 37:19-22.
20 Flyger, V. 1964. Urban sprawl endangers native Maryland mammals.
Maryland Conserv., 41:6-7.
21 Taylor, G.J. 1976. Range determination and habitat description of
the Delmarva fox squirrels in Maryland. M.S. Thesis, Univ. of MD.,
College Park.
22 Rhoads, S.N. 1903. The mammals of Pennsylvania and New Jersey.
Privately published, Philadelphia.
23 Abbott, C.C. 1890. In: The Geological Survey of New Jersey. J.
Nelson, ed. 1890. Vol. 2. Part 2:500. The John Murphy Co.,
Trenton.
24 Rhodes, L. 1971. Delmarva Peninsula fox squirrel study,
Blackwater NWR. U.S. Dept. of Interior, Bureau of Sport Fisheries
and Wildl. Final report.
25 Eyre, F.H., ed. 1980. Forest cover types of the United States and
Canada. Soc. of Amer. Foresters. 148 pp.
26 Maryland Dept. of Agriculture. 1982. Maryland Agricultural
Statistics Summary for 1981. MD Crop Reporting Service. 56 pp.
27 Smith, C. and D. Follmer. 1972. Food preferences of squirrels.
Ecology 53:82-91.
28 Asdell, S.A. 1964. Patterns of mammalian reproduction. 2nd ed.
Cornell Univ. Press. 670 pp.
29 Tacha, Martha C. 1983. Personal field notes, 1981-1982. U.S.
Fish and Wildlife Service, 1825 Virginia St., Annapolis, MD 21401.
30 Handley, C.O. and L.K. Gordon. 1979. In: Endangered and
threatened plants and animals of Virginia. D. Linzey, ed. VPI&SU,
Blacksburg. Pp. 507-513.
31 Burt, W.H. and R.P. Grossenheider. 1964. A field guide to the
mammals. Houghton Mifflin, Boston. 284 pp.
32 Virginia Commission of Game and Inland Fisheries. 1982. Virgina
endangered species investigations, Delmarva fox squirrel. Unpubl.
Rept. Federal Aid Project No. EW-1-6-I-A. Pp. 436-441.
33 Lustig, L.W. and V. Flyger. 1975. Observations and suggested
management practices for the endangered Delmarva fox squirrel.
Proc. 29th Ann. Conf. Southeastern Assoc. of Game and Fish
Commissioners:433-440.
34 Flyger, Vagn. 1983. Pers. comm. Professor of Wildlife Biology,
Animal Science Dept., Univ. of MD, College Park, MD 20742. (301)
454-7844.
35 Moser, G. Andrew. 1983. Pers. comm. U.S. Fish and Wildlife
Service, 1825 Virginia St., Annapolis, MD 21401.
36 U.S. Fish and Wildlife Service. Sept. 13, 1984. Determination of
experimental status for an introduced population of Delmarva fox
squirrel. Department of Interior, U.S. Fish and Wildlife Service.
Fed. Reg. 49:36418-36420.
37 Hall, E.R. 1981. The mammals of North America. 2nd ed. Vol. 1.
John Wiley and Sons, New York. 428 pp.
38 Jacobs, J. 1988. Pers. comm. USFWS, Annapolis, MD. 21401.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 U.S. Fish and Wildlife Service. 1983. Delmarva Peninsula Fox
References - 2 (DRAFT) - References
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
Squirrel Recovery Plan. U.S. Fish and Wildlife Service, Newton
Corner, MA. 49 pp.
02 Field records on file at: U.S. Fish and Wildlife Service,
Annapolis Field Office, 1825 B Virginia St, Annapolis, MD 21401.
03 Taylor, Gary J. 1983. Pers. comm. Maryland Wildlife
Administration, Wye Mills Work Center, P.O. Box 68, Wye Mills, MD
21679. (301) 827-8612.
04 Poole, E.L. 1944. The technical names of northeastern fox
squirrels. J. Mammal. 25(3):315-317.
05 Paradiso, J.L. 1969. Mammals of Maryland. North American Fauna
No. 66. U.S. Dept. of Interior, Bureau of Sport Fisheries and
Wildl., U.S. Gov. Printing Office, Washington, D.C. 193 pp.
06 Taylor, G.J. 1973. Present status and habitat survey of the
Delmarva Fox Squirrel (Sciurus niger cinereus) with a discussion of
reasons for its decline. Proc 27th Annal Conf. of the Southeast
Assoc. of Game and Fish Commissioners. Pp. 278-289.
07 Sheffer, Dale E. 1983. Pers. comm. Division of Game Management,
Pennsylvania Game Commission, P.O. Box 1567, Harrisburg, PA 17120.
(717) 787-5529.
08 Barkalow, F.S., Jr. 1956. Sciurus niger cinereus Linne neotype
designation. Proc. Biol. Soc. of Washington 69:13-20.
09 Hall, E.R. 1981. The mammals of North America. 2nd ed. Vol. 1.
John Wiley and Sons, New York. 428 pp.
10 Rhoads, S.N. 1903. The mammals of Pennsylvania and New Jersey.
Privately published. Philadelphia.
11 Van Gelder, Richard G. 1983. Pers. comm. Chairman and Associate
Curator, Dept. of Mammalogy, Amer. Mus. of Natural History, Central
Park West, 79th Street, New York, NY 10024. (212) 873-1300.
12 Hennesy, Rod. 1983. Virginia Coast Reserve, The Nature
Conservancy, Brownsville, Nassawadox, VA 23413 (804) 442-3049.
13 Mansueti, R. 1952. Comments on the fox squirrels of Maryland. MD
Conservancy, 22:30-41.
14 Dozier, H.L. and H.E. Hall. 1944. Observations on the Bryant fox
squirrel, Sciurus niger bryanti Bailey. MD Conservancy, 21:1-12.
15 Taylor, G.J. and V. Flyger. 1973. Distribution of the Delmarva
fox squirrel (Sciurus niger cinereus) in Maryland. Chesapeake Sci.
14:59-60.
16 Handley, C.O., Jr. and L.K. Gordon. 1979. In: Endangered and
threatened plants and animals of Virginia. VPI & SU, Blacksburg.
D. Linzey, ed. Pp. 507-513.
17 Flyger, Vagn. 1983. Pers. comm. Professor of Wildlife Biology,
Dept. of Animal Science, Univ. of MD, College Park, MD 20742.
(301) 454-7844.
18 Flyger, V. and D.A. Smith. 1980. A comparison of Delmarva fox
squirrel and gray squirrel habitats and home range. Trans. of the
Northeast Section of the Wildlife Society, 37:19-22.
19 Audubon, J.J. and J. Bachman. 1854. The quadrupeds of North
America. 383 pp. Text and paintings reprinted In: The imperial
collection of audubon animals. V.H. Cahalane, et al. 1967.
Bonanza Books, New York. 307 pp.
20 U.S. Fish and Wildlife Service. Sept. 13, 1984. Determination of
experimental status for an introduced population of Delmarva fox
squirrel. Department of Interior, U.S. Fish and Wildlife Service.
References - 3 (DRAFT) - References
Species SQUIRREL, FOX, DELMARVA PENINSULA
Species Id ESIS055001
Date 14 MAR 96
Fed. Reg. 49:36418-36420.
21 Jacobs, J. 1988. Pers. comm. USFWS, Annapolis, MD. 21401.
References - 4